How to exit an Android app programmatically?

Question

I am sure this question has been asked number of times because I read a few. My client wants me to put a button into his app where users can click and exit. I have read this

Answer 1

put this one into your onClic:

moveTaskToBack(true);
    finish()

Answer 2

ghost activity called with singletop and finish() on onCreate should do the trick

Answer 3

Just call these two functions

 finish();
 moveTaskToBack(true);

Answer 4

If you use both finish and exit your app will close complitely

finish();

System.exit(0);

Answer 5

finish();
 finishAffinity();
 System.exit(0);

worked for me

Answer 6

 @Override
    public void onBackPressed() {
        AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
        alertDialogBuilder.setTitle("Exit Application?");
        alertDialogBuilder
                .setMessage("Click yes to exit!")
                .setCancelable(false)
                .setPositiveButton("Yes",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                moveTaskToBack(true);
                                android.os.Process.killProcess(android.os.Process.myPid());
                                System.exit(1);
                            }
                        })

                .setNegativeButton("No", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {

                        dialog.cancel();
                    }
                });

        AlertDialog alertDialog = alertDialogBuilder.create();
        alertDialog.show();
    }